The present invention refers generally to a load hoisting apparatus, and in particular to a load hoisting apparatus for allowing manual maneuvering of a load, having a handle connected to the load via a load-engaging member, and a lifting mechanism for compensating the weight force of the load.
In conventional load hoisting devices, a load sensor is positioned between the lifting mechanism and the load-engaging member for transmitting an electric signal commensurate with a registered load value to a control unit to so operate the hoisting apparatus that the load is maintained in balance. Typically, the handle, which is designed in the form of a grip, and the load sensor form separate structural components, with the handle being situated, as viewed in direction of the force flow, either immediately above the load sensor, or projecting laterally out from an upper area of the load-measuring unit that includes the load sensor.
These types of conventional load hoisting devices are disadvantageous in several aspects. A superimposed disposition of the load sensor and the handle results in an increase of the distance between the handle and the load-engaging member so that the possible lifting height is decreased and the operator must apply greater forces in order to swing the load about a horizontal axis. In case the handle projects laterally outwards from the load measuring unit, a lifting or lowering of the load results in a tilting motion of the load so that as a consequence of inertia a recoil action is experienced that leads to faulty signals when compensating the weight force and to error commands from the control system.